Chromatography Forum

I do have a question for you...

Does the retention time of your last impurity remains the same or changes over time? Does the intensity/peak area change when you equilibrate more your column or not? What about the main and the impurities retention time? Do they remain the same or drift to higher retention times over time (which could explain the tailing).

- the retention time of the last impurity does not change over time
- the peak area is independent on the equilibrium time
- the retention times of all other compounds (main and other imp) remain constant

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I just visited the URL of the manufacturer of the ion-pairing reagent. They claim to act as supplier for:

- paint thinners
- paints / lacquers
- cleaning agents

Thus, a change of supplier might really be a good idea...

If changing the supplier solves the problem – as you describe it, it would be more art than science. Apropos paint industry

Best Regards